The proposed research is a continuing study of factors which may be responsible for the observed loss of cardiac contractility in congestive Heart Failure. This project uses both the surgically induced canine failure model as well as the Bio 14.6 cardiomyopathic hamster in which to study the alteration of the sarcolemma, sarcoplasmic reticulum and contractile proteins during failure. More specific the electrolyte "pumping" mechanisms and the effect of Taurine (2-aminoethane sulfonic acid) on any alterations found.